Jung SY, et al. – In previous studies, researchers have shown that obesity-insulin connections may be potential risk factors for postmenopausal breast cancer, and the link between insulin resistance (IR) genotypes and phenotypes may be modifiable via obesity-lifestyle factors, affecting breast cancer risk. Investigators of the current study, therefore, examined the role of IR in those pathways at the genome-wide level. Overall 58 loci for associations with IR phenotypes (homeostatic model assessment-IR, hyperglycemia, and hyperinsulinemia) were previously identified and used in this study. The most common influential factors identified were two single-nucleotide polymorphisms (SNPs; LINC00460 rs17254590 and MKLN1 rs117911989), exogenous factors related to lifetime cumulative exposure to estrogen, body mass index, and dietary alcohol consumption. No significant associations of individual SNPs with breast cancer were identified, but a synergistic impact of SNPs and lifestyles combined resulted in increased risk of breast cancer in a gene-behavior, dose-dependent manner.